Childhood lead poisoning remains a serious problem in the U.S. About 25,000 children are diagnosed annually as lead poisoned and about 2,500 receive chelation therapy. There is a need for safer and more effective chelating agents to be used in treatment of this disease. Use of currently available chelating agents is limited by at least two factors. First, the agents are reasonably toxic. Second, they are nonspecific chelators of a variety of metals so that treatment with these agents can be produce secondary deficiencies of essential metals. In the proposed research, the usefulness of 2,3-dimercapto propane-1-sulfonate (DMPS) in the treatment of childhood lead poisoning will be examined. Available data suggest that this agent is safe for use in man and that it is an effective chelator of lead. Primary goals of the proposed research will be to determine the ability of DMPS to promote decorporation of lead and to reverse the biochemical indicators of lead poisoning. The effect of DMPS on th excretion of the essential metals, zinc and copper, will also be examined. Since data are available in this laboratory on the effectiveness of calcium disodium ethylene diamine tetraacetate in the treatment of childhood lead poisoning, it will be possible to make direct comparison of the safety and efficacy of the two chelating agents. The availability of a new and safe chelating agent such as DMPS would be of considerable value in the management of childhood lead poisoning. The proposed research could contribut notably to this effort.